Equipment such as solder printers, component mounters, reflow ovens, and board inspection machines is used to produce boards mounted with many electronic components. Conventionally, this equipment is connected to configure a board production line that acts as an electronic component mounting system. Among this equipment, component mounters provided with a board conveyance device that includes a conveyance lane for loading and unloading boards, and a component transfer device including a mounting head that picks up electronic components from a component supply device and mounts them on a board are typical. In order to support an increase in the types of electronic components mounted on a single board, electronic component mounting system configured from multiple connected component mounters are common. Further, in order to produce two types of boards in parallel, there are also electronic component mounting system configured from multiple connected component mounters equipped with dual conveyance lanes and twin mounting heads. With electronic component mounting systems that produce two types of boards in parallel, an independent production method and a dual production method are already known.
With an independent production method, a first board loaded into a first conveyance lane is mounted with electronic components using a first mounting head, and a second board loaded into a second conveyance lane is mounted with electronic components using a second mounting head. Thus, operators are able to handle the first conveyance lane and the second conveyance lane as separate independent board production lines. In other words, this allows for the production speeds of the boards to be different for the first conveyance lane and the second conveyance lane. Also, when the type of board being produced changes, operators are able to perform changeover work for each conveyance lane independently.
Conversely, with a dual production method, first, electronic components are mounted onto a first board loaded into a first conveyance lane using a first mounting head and a second mounting head, during which time a second board is loaded into a second lane. When mounting onto the first board is complete, electronic components are mounted onto the second board loaded into the second conveyance lane using the first mounting head and the second mounting head, during which time the completed first board is unloaded from the first conveyance lane and the next board is loaded. Thereafter, mounting is performed using the first mounting head and the second mounting head alternately at the first conveyance lane and the second conveyance lane.
The two production methods above each have advantages and disadvantages. For example, an independent production method has an advantage in that it is possible to perform changeover work at the second conveyance lane while the first board is being produced at the first conveyance lane. On the other hand, an independent production method has a disadvantage in that the mounting heads are idle in a standby state when boards are being loaded into each conveyance lane. Conversely, a dual production method has an advantage in that mounting heads are not in a standby state while boards are being loaded and unloaded. On the other hand, a dual production method has disadvantages in that the production speeds of the first board and the second board cannot be changed, and complex control is required to prevent the mounting heads from interfering with each other, with mounting heads needing to be in a standby state in order to avoid interference. Due to the above, it is desirable to use the more efficient production method considering conditions such as the type of board, production quantity, and effort required for changeover work. Technology for improving a production method in order to improve board production efficiency of an electronic component system equipped with dual conveyance lanes and twin heads is disclosed in patent literature 1 and 2.
Disclosed in patent literature 1 is a component mounting system provided with multiple component mounting devices lined up, the component mounting devices being provided with a board conveyance conveyor configured from a board conveyance path along which multiple types of boards are conveyed, and multiple component mounting means that perform consecutive mounting of components onto multiple types of boards. Each component mounting device of this component mounting system provided with multiple component mounting means performs component mounting operations with respect to one type of board, with each board conveyance path being established such that each type of board is conveyed separately. Further, in the embodiment disclosed in FIG. 1 of patent literature 1, from the six component mounters lined up, the first mounter and the fourth mounter are dedicated for board 3a of board conveyance path La, the second mounter and the fifth mounter are dedicated for board 3b of board conveyance path Lb, and the third mounter and the sixth mounter are dedicated for board 3c of board conveyance path Lc. Due to this, each component mounting device provided with multiple component mounting means only performs component mounting for one type of board, thus mounting mistakes are unlikely to occur, meaning that the good product production rate is improved compared to previous technology.
Patent literature 2 discloses a mounting conditions determining method for determining mounting conditions at a production line provided with multiple component mounters that each include multiple conveyance lanes. This mounting conditions determining method includes a step for allocating board types to each set of conveyance lanes formed from a series of paths, a setting step for setting each of the multiple component mounters as a dedicated device that performs mounting for only one type of board, and a step for determining the quantity of dedicated devices and the quantity of shared devices by changing multiple dedicated devices for at least one shared device. Further, in the embodiment shown in FIGS. 14 and 15 of patent literature 2, from the six connected component mounters, the first mounter and second mounter are dedicated for the R lane, the third mounter and fourth mounter are dedicated mounters for the F lane, and the fifth mounter dedicated for the R lane and the sixth mounter dedicated for the F lane are changed for a single shared device. Thus, it is possible to maintain a high maximum operating rate for all the component mounters while limiting the arrangement space required for the mounters, and maximize the quantity of dedicated mounters that have excellent changeover functionality, while limiting the overall quantity of component mounters.